Straight Talk Articles

Questions to Ask When Purchasing a New Home
July, 2017

Dear Pat:

I recently became a real estate agent and several of my clients have been asking about the energy efficiency of the homes I show them.  Do you have any suggestions about what energy-related questions I should help my clients consider before they buy a home? 



Dear Sharon:

It is great that you want to help better inform your clients!  Many home buyers don’t consider this fact: energy costs (such as electricity, gas, and propane) are the most significant home operating expense. The average home pays $2,478 in energy costs per year. Think about how much money that is over the life of the home.


Your client’s preferences about the kind of new home they want to buy can have a strong influence on the energy performance of the home.  For example, the size of a home is one of the most important factors that will determine energy costs.  As square footage increases, lighting requirements increase and most importantly—the burden on heating and cooling equipment rises. 


In general, newer homes have better energy performance due to advancements in building codes, but buying a new home is not a guarantee of efficiency.  Codes are sometimes not enforced, and a minimum code home is not nearly as efficient as homes built to a higher standard.  Also, some newer homes have been built to certain specifications that ensure a higher level of energy performance than homes built to code. For example, if energy efficiency or green features are a very high priority for your clients, look for homes that have ENERGY STAR, Built Green, or Leadership in Energy and Environmental Design (LEED) certifications.


On the flip side, manufactured homes can be problematic from an energy efficiency standpoint.   Residents of manufactured homes spend about 70 percent more on energy per square foot of living space as residents of site-built homes. If your clients are considering a manufactured home, those built after 1994 or that have an ENERGY STAR label have superior energy performance. 


Once your clients are interested in a specific home, one of the first questions you should ask is, “how does the energy performance of this home compare to similar homes?”  Although you may request electricity, natural gas, or propane bills from the sellers so that your clients can estimate how much it will cost to heat and cool the home annually, this is an imprecise measure of home energy performance.  The Home Energy Rating System (HERS) Index is like a miles per gallon rating for a home that allows consumers to comparison-shop for homes based on energy performance, the way they can for cars.  A certified RESNET Home Energy Rater will need to inspect the home and develop a HERS rating.  This rating can be done during the inspection process or you may request a HERS rating from the sellers. 


Although many home buyers focus on energy features of the home that have the strongest impact on the aesthetics of the home (e.g., windows and lighting fixtures), it is the hidden systems, appliances, and features of the home that have the most impact on home energy performance. Heating and cooling systems consume about half of a home’s energy use and are costly to replace.  Here are some good questions to consider about heating and cooling:

  • How old is the heating system?: If the house’s heating system is more than 10 to 15 years old, it may be necessary to replace it in the near-term.

  • Find out the seasonal energy efficiency rating (SEER) for the house’s air conditioning system: If the air conditioner has a SEER of less than 8 you will likely want to replace it.


A home's building envelope insulates the home's interior from the outdoor environment and includes features like doors, walls, and the roof.  If the quality of the building envelope is compromised, it can contribute to higher heating and cooling costs.  R-Value is the thermal resistance measurement used for insulation, indicating its resistance to heat flow.  You may want to learn what the recommended R-value is for homes in your region so you will have a general sense about the quality of a home’s building envelope. 


If your clients determine that they are going to need to make energy investments in a home they are considering, it can be helpful to call your local co-op.  Many co-ops can assist with energy audits in some capacity and offer incentives for energy efficient heating and cooling equipment. 


This column was co-written by Pat Keegan and Christine Grant of Collaborative Efficiency.

A home energy rater can help you understand the energy performance of a home.  Photo credit:  United Cooperative Service